moonlight-qt/app/streaming/input/sdlinputsubsystems.cpp

#include "streaming/input/sdlinputsubsystems.h"

#include "settings/mappingmanager.h"

namespace {

int s_JoystickRefs = 0;
int s_GameControllerRefs = 0;
#if !SDL_VERSION_ATLEAST(2, 0, 9)
int s_HapticRefs = 0;
#endif

bool retainSubsystem(Uint32 subsystem, int& refs, const char* subsystemName, const char* ownerTag)
{
    if (refs == 0 && SDL_InitSubSystem(subsystem) != 0) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
                     "Failed to initialize %s subsystem for %s: %s",
                     subsystemName,
                     ownerTag,
                     SDL_GetError());
        return false;
    }

    refs++;
    return true;
}

void releaseSubsystem(Uint32 subsystem, int& refs, const char* subsystemName, const char* ownerTag)
{
    if (refs <= 0) {
        SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION,
                    "Ignoring unbalanced release of %s subsystem for %s",
                    subsystemName,
                    ownerTag);
        refs = 0;
        return;
    }

    refs--;
    if (refs == 0) {
        SDL_QuitSubSystem(subsystem);
    }
}

}

namespace SdlInputSubsystems {

bool acquire(const char* ownerTag, const LeaseOptions& options)
{
    bool acquiredJoystick = false;
#if !SDL_VERSION_ATLEAST(2, 0, 9)
    bool acquiredGameController = false;
    bool acquiredHaptic = false;
#endif

    if (options.joystick) {
        if (!retainSubsystem(SDL_INIT_JOYSTICK, s_JoystickRefs, "joystick", ownerTag)) {
            return false;
        }
        acquiredJoystick = true;
    }

    if (options.gameController) {
        if (!retainSubsystem(SDL_INIT_GAMECONTROLLER, s_GameControllerRefs, "gamecontroller", ownerTag)) {
            if (acquiredJoystick) {
                releaseSubsystem(SDL_INIT_JOYSTICK, s_JoystickRefs, "joystick", ownerTag);
            }
            return false;
        }
#if !SDL_VERSION_ATLEAST(2, 0, 9)
        acquiredGameController = true;
#endif
    }

#if !SDL_VERSION_ATLEAST(2, 0, 9)
    if (options.haptic) {
        if (!retainSubsystem(SDL_INIT_HAPTIC, s_HapticRefs, "haptic", ownerTag)) {
            if (acquiredGameController) {
                releaseSubsystem(SDL_INIT_GAMECONTROLLER, s_GameControllerRefs, "gamecontroller", ownerTag);
            }
            if (acquiredJoystick) {
                releaseSubsystem(SDL_INIT_JOYSTICK, s_JoystickRefs, "joystick", ownerTag);
            }
            return false;
        }
        acquiredHaptic = true;
    }
#endif

    if (options.applyMappings) {
        MappingManager mappingManager;
        mappingManager.applyMappings();
    }

    if (options.flushControllerDeviceEvents) {
        SDL_FlushEvent(SDL_CONTROLLERDEVICEADDED);
        SDL_FlushEvent(SDL_CONTROLLERDEVICEREMOVED);
    }

    return true;
}

void release(const char* ownerTag, const LeaseOptions& options)
{
#if !SDL_VERSION_ATLEAST(2, 0, 9)
    if (options.haptic) {
        releaseSubsystem(SDL_INIT_HAPTIC, s_HapticRefs, "haptic", ownerTag);
    }
#endif

    if (options.gameController) {
        releaseSubsystem(SDL_INIT_GAMECONTROLLER, s_GameControllerRefs, "gamecontroller", ownerTag);
    }

    if (options.joystick) {
        releaseSubsystem(SDL_INIT_JOYSTICK, s_JoystickRefs, "joystick", ownerTag);
    }
}

bool hasExclusiveGamepadOwnership()
{
    if (s_JoystickRefs != 1 || s_GameControllerRefs != 1) {
        return false;
    }

#if !SDL_VERSION_ATLEAST(2, 0, 9)
    if (s_HapticRefs != 1) {
        return false;
    }
#endif

    return true;
}

bool reenumerateGamepadSubsystems(const char* ownerTag)
{
    if (!hasExclusiveGamepadOwnership()) {
        SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION,
                    "Skipping subsystem re-enumeration for %s due to shared ownership (joystick=%d gamecontroller=%d)",
                    ownerTag,
                    s_JoystickRefs,
                    s_GameControllerRefs);
        return false;
    }

#if !SDL_VERSION_ATLEAST(2, 0, 9)
    SDL_QuitSubSystem(SDL_INIT_HAPTIC);
#endif
    SDL_QuitSubSystem(SDL_INIT_GAMECONTROLLER);
    SDL_QuitSubSystem(SDL_INIT_JOYSTICK);

    if (SDL_InitSubSystem(SDL_INIT_JOYSTICK) != 0) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
                     "Failed to reinitialize joystick subsystem for %s: %s",
                     ownerTag,
                     SDL_GetError());
        return false;
    }

    if (SDL_InitSubSystem(SDL_INIT_GAMECONTROLLER) != 0) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
                     "Failed to reinitialize gamecontroller subsystem for %s: %s",
                     ownerTag,
                     SDL_GetError());
        return false;
    }

#if !SDL_VERSION_ATLEAST(2, 0, 9)
    if (SDL_InitSubSystem(SDL_INIT_HAPTIC) != 0) {
        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
                     "Failed to reinitialize haptic subsystem for %s: %s",
                     ownerTag,
                     SDL_GetError());
        return false;
    }
#endif

    MappingManager mappingManager;
    mappingManager.applyMappings();

    SDL_JoystickUpdate();
    SDL_GameControllerUpdate();

    SDL_FlushEvents(SDL_JOYDEVICEADDED, SDL_JOYDEVICEREMOVED);
    SDL_FlushEvents(SDL_CONTROLLERDEVICEADDED, SDL_CONTROLLERDEVICEREMAPPED);

    return true;
}

}